Stripper pin for sheet feeding machines



Oct. 6, 1953 M. J. AJAM ETAL 2,654,600

STRIPPER PIN FOR SHEET FEEDING MACHINES Filed July 14, 1950 2 Sheets-Sheet 1 INVENTORS 60/! 4 fiery/nan BY 9m, flaw 3W ATTORNEYS 1953 M. J. AJAM ET AL STRIPPER PIN FOR SHEET FEEDING MACHINES 2 Sheets-Sheet 2 Filed July 14, 1950 INVENTORS. Mustard J 4/4/11 far/ (i 6660' 2 BY (Q/vm /"m ATTORNEYS u-mree Patented Oct. 6, 1953 1 The present invention relates'tddevi'ces, "conveniently referred to as"stripper pins','whi-ch' are used with machines in which the sheets of-a pack or. pile of sheets are fed'from the top oneby'one, the feeding being done ordinarilyby an" automatic feeder having a' feed 'foot restingon'the top sheet of the pack. 'Ihe function of 'the"stTipper. pin isto assist in separating the top" sheet from the pack and toprev'eht more" than one sheet at a time being fed forward.

' In the past a cOnSiderame'Varityibf' devices for' this purpose have been 'usedbut they-have been defective in one" respe'ctor' another and have failed to erform their intended function satisfabtorily or have-notbeen adaptableito' different conditions, for instance; d'ifferences"'in"quality, thickness, stiffness, and weight" and surface"of the'paper, andhave" been easily effected by variations inmoisture' and static.

' The present invention-therefore"hasfor its "object toprovidea stripper pin" which wilibe'le'ss efiected' b such variations" and""'which"'willbe satisfactory in 'use under widely varying 'condi tions. In particular the invention providesa device'which' will work satisfactorily andwithout any adjustment by the operator with paper varying in weight from letter paper to eardb'oardeven when sheets "of difierent weight are "included "in the same pack. As far as we are aware'th'ishas never been accomplished before.

Theinvention will'be understood by reference to the accompanying drawings in which the-device is shown in connection with'the' essential parts of a fluid duplicating machine," this being a convenient way to illustrate the construction and mode of operation of the device, but it will be understood that the device may be' usefu lly employed in connection with other machines in *which sheets are fed one-by-onefrom the top of a pile or pack.

In the drawings:

Fig. 1 is a plan view of a portion of a duplicating machine showing the stripper pin embodying my invention in relation to the essential parts of the machine, the front of the machine being at the right.

Fig. 2 is a section on line 22 of Fig. 1 looking in the direction of the arrows.

Fig, 3 is an enlarged view similar to Fig. 2 to illustrate the action of the stripper pin when a relatively thin sheet is being fed, the thickness of the sheet being exaggerated for clarity of illustration.

Fig. 4 is a View similar to Fig. 3 showing the action of the stripper pin when a sheet of cardboard or tag stock is being fed.

1 2 Z'Figf-Sds .a section on 'Iine 55"of"Fig.4 looking'down.

: Fig.6 is a top plan view. or thestrippen pin. 'Figf '7 is a side elevation bf the stripper pin 6 looking" from the left side of the machine.

- FigfSis a rear elevation of the stripper 'p'in. FigIQ- is'a View in perspective of the flexible blade or-gate'forming part ofthe 'st'ripper'pin.

Referring now to the drawings' andirparticupaper resting in the fed tray H ,andL at" 13 is shown the side guideagainstwhich the" edge. 'of the. paper r'e'sts'andby' which 'itlis"'gu'idedasit moves forward. At '15 and I 6 are shownthe' feed rolls "and at- [8 ai'guide for the'paper leading from the bottom of'the' fd'tray' l ftdthebi'te'ofthe feedtrolls 15am l6. The paper isfed" forward sheet by sheet by a reciproeatin'gfeed foot l9 'inChidl-ng Iubb'erfedldHs '2 E and" 2 l"'which d0 not rotate when the feed footie" moving forward,

i. e; toward the rightirfFi'gsI 1" and 2' but are free to 'rotatewhenthe' feed foot 19 isbeing drawn back, i. e; 130' the left'in Figsf 1 Eind Z. "The" 'fed foot I9 is moved forward and back by suitable actuatingmechanism attached to arm 23. It will be'und'erstood "that" theselpa'rts' are i of "ordinary construction andfor'm no part of the" present invention.

" The" stripperipinembodying thpre's'ent'inven- 'a round shaft 24 having" a longitudinal "'slot 25 m ned in one side. 'In this slotis'se'cured abody '26 having on the' to p a horizontal*handle 2 I by 1 which "the entire stripper" pin "maybe-lifted as 35 "required. Justbelow" thehandlefl is a -lug 28 in the plane of the body. About midwayofiits length thebody 25 is offset as shownatZQ to form" an arm swwhiehiies"over'thesidemargin of the. paper'A and extendsrearwardly aswill be seen from'the plan"vi'wf Fig. 6. This"ar'm3fi"is also bent downwardly as shown in Fig. '7. At the rear end of the arm 30 is a roller 3| carried on a pin 32 on the arm. This roller is free to rotate on the pin. Directly below the offset portion 29 5 of the body 26 is a projective 34 to which is secured a flexible blade 35. This blade is shaped as shown in Fig. 9 and is thin and preferably of spring steel so that it can bend under pressure from the top sheet when required but will return at once to its original position. The blade is also narrowed toward the top to increase its flexibility. A slot 36 is formed in the blade and the blade is secured to the projection 34 by two screws 31, 3'! and thus may be adjusted vertically. The blade 5 is adjusted so that its upper end or tip 38 lies slightly above the bottom of the roller 3| on the ofiset arm 30. This difference in level is indicated by dash lines in Fig. 8 and in practice is usually about 3% of an inch.

The stripper pin is located in a suitable hole in the side guide l3 adjacent the pack of paper A, with the roller 3| resting on the top sheet. The stripper pin is free to slid vertically in the hole in the side guide l3, but is prevented from turning about its longitudinal axis by the body 26 which is in the slot which intercepts the hole in which the pin slides. The front edge of the pack A rests against the back face of the blade 35 with its tip 38 slightly above the level of the top sheet of the pack and, as already explained, slightly above the lowest point of the roller 31. When the top sheet B (see Fig. 3) is a thin sheet of stock such as letter paper, and is fed forward by the rubber rollers 20 and 2| of the feed foot [9, the front edge of the sheet strikes the tip 38 of the blade 35 and the further forward movement of th sheet buckles the portion of the sheet between the roller 3| and the blade 35 without any appreciable bending of the blade until the front edge of the sheet snaps over the blade and allows the sheet to be fed into the bite of the feed rolls I5 and it, the position of the sheet at this time being indicated by the dotted lines in Fig. 3. When the top sheet 0 (see Fig. 4) is a. thick one, for instance card or tag stock, and therefore stiffer,

it buckles little or not at all and the pressure of the front edge of the sheet against the tip 33 of blade 35 bends the blade forward slightly so the rear surface has a slight upward inclination which assists the sheet to snap over 0 the tip of the blade. In this manner the sheets comprising the stack will be fed one at a time, even if the stack is composed of thin sheets or thick sheets or of sheets of different thicknesses, and no adjustment is required for different thicknesses of sheets. As the stack is reduced in thickness, the stripper pin lowers itself little by little with the roller 3| resting on the top sheet of the pack, but the relation of the blade tip 38 to the bottom of the roller 3| and hence to the level of the top sheet in the pack always remains the same.

When for any reason, the stripper pin is not required, as for instance when the operator wishes to feed the sheets by hand, the stripper pin is allowed to drop through the cut-out 39 in the corner of the feed tray (see Fig. 1) and lug 28 comes to rest on guide l3 as shown dotted in Fig. 8. This removes the pin from the front of the pack of paper.

We claim:

1. The stripper pin for machines in which the sheets of a pack of sheets are fed one by one from the top which includes in combination a member slidable vertically in a fixed portion of the machine adjacent the side of the pack, a portion of said member resting on the top sheet of the pack at a point in the rear of the leading edge of the sheet, and a flexible blade carried by the vertically sliding member and located in contact with the front face of the pack, the top edge of the flexible blade being slightly above the point of contact of that portion which rests on the top sheet of the pack.

2. In a duplicating machine having a feed tray for a pack of sheets, a fixed side guide, therefore, and a reciprocating feed foot, and in combination therewith a stripper pin to separate the top sheet of said pack, said stripper pin comprising a post vertically slidable in said side guide, a contact finger resting on the top sheet of said pack at a point at the rear of the leadin edge of the pack, and a flexible gate carried by said post and in contact with the front face of the pack, the top edge of the gate being slightly above the point of contact of the contact finger with the top sheet of the pack.

3. In a machine for feeding sheets one by one from the top of a pack, the improved stripper pin having a roller resting on the top sheet of the pack at a point in the rear of the leading edge of the sheet and a blade resting against the front of the pack with its tip slightly above the bottom of said roller and capable of being bent forward by the pressure of the top sheet as the sheet is fed forward, said stripper pin being slidable vertically and being supported by the contact of the roller with the pack of sheets.

4. The stripper pin for machines in which the sheets of a pack of sheets are fed one by one from the top which includes in combination a member slidable vertically in a fixed portion of the machine adjacent the side of the pack at the forwardcorner thereof, a portion of said member resting on the top sheet of the pack at a point in the rear of the leading edge of the sheet, and a flexible blade carried by the vertically sliding member and located in contact with the front face of the pack, the top edge of said blade being slightly above the point of contact of that portion which rests on the top sheet of the pack.

MUSTAFA J. AJAM. CARL A. BERGMAN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 679,961 French Aug. 6, 1901 2,080,968 Krell May 18, 1937 2,166,272 Storck July 18, 1939 2,343,187 Jagger Feb. 29, 1944 

